Railway signaling



May 6 1924. 1,492,940

E. C. SASNETT RAILWAY SIGNALING Filed Dec, 7, 1922 Patented May 6, 1924.

EDWARD 0.. sAsNn'r'r,oFwAsHING'roN, DISTRICT or COLUMBIA,

RAILWAY SIGNALING.

Application filed December 7, 1-922. Serial No. 605,482.

The object of my invention is to provide a continuous indication third rail system having provisions to ire-vent the reception of a false indication 5y a following train when it enters an occupied block. To this end, the system of the present invention includes means responsive to the entry of a train into an occupied blockto control the signaling energy supplied to the third rail section pertaining to that block. This means may comprise an electro-respons1ve device controlled jointly by at least two adaccnt track relays, in such a manner that said device will be energized, or if alreadyenergized, will remain energized, when a train actuates said relays in accrtain sequence, but whichwill be deenergized if a second train should actuate the first relay While the second relay is still under the control of the "first train. An electro-responsive device controlled in this manner is'adapted to other uses than the specific use disclosed herein, and I therefore intend to make broad claims for this element ofthe system.

Referring to the accompanying drawing, which illustrates diagrammatically aform of my invention i The track is divided by insulated joints into sections A, A, B, B etc. 'The sections A, A constitute a block and the sections B, B, a succeeding block. The sections A,

B are preliminary sections and are relatively short as compared with sections A, B. Each section forms part of a closed track circuit, which includes a track battery at one end and a track relay at the other end. As is well understood, when a train enters a section the wheel's and axles thereof short circuit the track battery and cause the track relay to be deenerglzed and thereby to open its front contacts and close its back contacts. v

For the purpose ofillustrating the application of my invention to continuous ind ication .train controlling systems, I have shown a signal conductor S, or third rail,

supported adjacent and parallelto the track in any approved manner and divided into insulated sections corresponding tothe block 7 other side to a shoe or trolley adapted to contact the conductor S. The electro-responsive device may be a relay having a neutral armature adapted to apply the brakes when opened, and a polarized armature adapted to display a caution signal or set in operation a speed limit device or both, in a manner which will be obvious to those skilled in the art.

The track relays C, D, C, D control stick relays E, F, E, F, and the relays F, F are adapted to connect batteries G, G, respectively, across the respective sections 'of signal. conductor S and the track, with one polarity or the other depending upon the direction of current through said relays. The system operates in the "following manner:

W'henthe train shown at the left enters section A and the two blocks ahead are closinga circuit through stick relay E from.

battery G byway of front contacts 1 and 2, line conductor 3, back contact 4, front contact 5, conductor 6, relay "E, common return R, front contact 8, front contact'9, conductor 10 to battery G. Relay E there'- upon picks up closing a stick circuit through itself exclusive of front contact 5, this circuit including back contact 4, front con-- tact'll and conductor 12 and being otherwise the same as the pick: up circuit just traced. The stick circuit'of relay E holds said relay energized when the; pick up circuit is broken at front contact 5 bythe entry of the train into section A. E will accordingly remain energized until the train passes entirely off section A, breaking the stickcircuit at back contact 4-. The energization of relay E closes the following circuit through relay F: battery G,

front contacts 1' and 2, conductor 3, front contact 13, relay F, common return, conductor 7, front contacts 8 and 9, conductor 10, batteryG'. Relay F then closes a stick circuit through itself exclusive of front contact 13, said circuit including front con- Belay tact 14, back contact 15, conductor 16, front contact 17, conductor 18, relay F, to common return. Hence relay F will remain energized when'the train wholly leaves section A causing the pick up circuit to be opened at front contact 1-3. When relay F picks up, battery G is connected across the signal conductor S and the track and the following circuit is completed: battery G, conductor 19, contact 20 of polarized armature, front contact 21 of the neutral armature, conductor 22, the track rails, the wheels and axle, relay 23, the sliding contacts 24, conductor S, conductor 2-5, front contact 26, polarized contact 27, conductor back to 'battery. The train entering block A, A will therefore receive a clear indication. If a train had been in section B", however, when the train under consideration entered section A, relay D would have been deenergized, and hence the direction of current through relay F would have been reversed, and the polarized armature of said relay would have made contact with 29 and 30 instead of 27 and 20. This would have reversed the direction of current through relay 23, opening the polarized contact thereof and displaying a cantion signal and setting in operation a suitable speed limit device or a device governed by the travel of the train which would cause the brakes to he set after a predetermined movement of said train in section A.

It will be observed that as long as the block A, A is occupied by a vehicle it is impossible for a second vehicle toenter this block under a clear indication. If a second vehicle should attempt to enter from the left, it would cause relay C to be deenergized, thereby breaking the retaining circuit of relay F at frcnt-contact 14. If a second vehicle should attempt to back into the bloci; from the right, the retaining circuit of relay F would be broken at front contacts 1 and 9. Hence it is clear that under no conditions is it possible for two vehicles in the same block to receive clear indications.

It is to be understood that the drawings are merely designed to show an illustrative example of the invention. Various modifications in the circuit arangements for controlling the eleetro-responsive device F are possible without changing the essential character of the invention. The invention is not concerned with the means for transmitt ng energy from the track to the control ling devices on the train. The conductive system shown is merely for the purpose of llustration, and it will be obvious that the invention is equally applicable to inductive systems or to systems of the radio type.

I claim:

1. In a block system, two adjacent track circuit sections, each includi a relay, an

electro-responsive device, means controlled by the track relays of said sections for en ergizing said device when a train enters the first track section and for retaining said de ice energized when the train passes on to the second track section and wholly off said first track section, and means for deenergizing said device when a second train enters said first track section while the first train is on said second track section.

2. In a block system, two adjoining trackcircuit sections, each including a relay, an electro-responsive device, an energizing circuit for said device controlled by the track relays of said sections and a retaining circuit for said device including a front contact of one of said relays, a back contact of the other relay and a contact which is closed only when said device is energized.

In a block system, two adjoining trackcircuit sections each including a relay, a relay having a pick-up circuit controlled by the track relays of said sections and a stick circuit closed only when said track relays are actuated in a certain sequence, said stick circuit including a front contact of one of said track relays.

l. In a block system, two adjoining trackcircuit sections, each including a relay, an electroresponsive device, means controlled by the track relays of both sect-ions for holding said device energized when a train enters the first track section and until it has passed entirely on to the second track section, a second electro-responsive device having a pick-up circuit controlled by the first mentioned device and a holding circuit controlled by bot-h of said track relays.

5. In a block system, two adjacent trackcircuit sections, each including a relay, relay having a pick-up circuit including back contact of the first track relay and front contact of the second track relay, holding circuit for said relay including a back contact of said first track relay and a front contact of said relay, asecond relay, a pick-up circuit for said second relay including a front contact of said first reand a holding circuit for said second relay including front contact of said first track relay, a back contact of said second track relay and a front contact of said second relay.

6. In a block system, a track divided into insulated blocks, each block comprising a short preliminary track section and a main traclr section and each section forming part of a closed track circuit including a track relay, an electro-responsive device for each block having an energizing circuit controlled jointly by the preliminary track re lay and the main track relay of the respective block, and a retaining circuit for said electro'rcsponsive device including in series a front contact of the preliminary track reion cuit for said auxiliary relay including a back contact of said preliminary track-section relay and a front contact of said.

auxiliary relay, an electro-responsive device, a pick-up circuit for said device including a front contact of said auxiliary relay, and a holding circuit for said device including a front contact of said preliminary tracl: section relay and a back contact of said main track-section relay.

8. A continuous indication block signaling system comprising a track divided into insulated sections each of which forms part of a closed track circuit including a relay,

each block being constituted by at least two track sections, an electro-responsive device for each block, means controlled by the track relays of a block for energizing the electroresponsive device of that block and maintaining said device energized when a train enters said block travelling in a given direction and until it passes into the block ahead, means for deenergizing said'device when a second train enters said block prior to the passage of the first train thereout, and a signaling circuit closed. by the energization of said device.

9. In a continuous indication block signaling system, two adjacent track circuit sections each including a relay, an electroresponsive device, means controlled by the track relays of said sections for energizing said device when a train enters the first track section and for retaining said device energized when said train passes on to thesecond track section and entirely oft said first track section said means being rendered inoperative to retain said device energized when a second train enters said first track section while the first train is on said second track section, means for supplying signaling energy to a train while passing over said track sect-ions when said device is energized, and a translating device on said train responsive to said energy.

10. In a continuous indication block signaling system, two adjoining track circuit sections each including a relay, an electroresponsive device, an energizing circuit for said device controlled by the track relays of said sections and a retaining circuit for said device including a front contact of one of said relays, a back contact of the 11; In a continuous indication block signaling system, two adjoining track cir- I cuit sections, each including arelay, a relay having a pick-up circuit controlled by the track relays of said sections and a stick circuit closed only when said track relays are actuated in a certain sequence, said stick circuit including a front contact of one of said track relays, means rendered operative by the energization of'said device for supplying energy to a train while passing over said track sections, and a translating device onsaid train responsive to said energy.

12. In a continuous indication block signaling system, two adjoining track circuit sections each including a relay, an electroresponsive device, means controlled by the trackrelays of both sections for holding said device energized when a train enters the first track section and until it has passed entirely on to the second track section, a second electroresponsive device having a pick-up circuit controlled by the first men-- tioned device and a holding circuitcontrolled by both of said track relays, means rendered operative by the energization of said second electro-responsive device for supplying energy to a train while passing over both of said track sections, and a translating device on said train responsive to said energy.

13. In a continuous indication block signaling system, a track divided into insulated blocks, each block comprising a short preliminary track section and a main track section and each section forming a. part of a closed track circuit including a relay, an electroresponsive device for each block having an energizing circuit controlled jointly by the preliminary track, section relay and the main track section relay oi the respective block, a retaining circuit for said electro-responsive device including in series a frontcontact of the preliminary track section relay and a back contact of the main track section relay, means rendered operative by the energization of said electrore sponsive device for supplying energy to a train while passing over the track sections of the block pertaining to said. device, and a translating device on said train responsive to said energy.

14. A continuous indication block signal ing system, comprising a track divided into &

an electro-responsive device for each block under the control of the track relays of the respective block and of the block in advance, means for energizing said device when a train enters the preliminary track section of the block pertaining thereto and for retaining said device energized during the passage of the train in said block, means rendered operative by the energization of said device for supplying signaling energy to a train during its passage over the block pertaining to said device, a translating device on said train responsive to said energy, and means for deenergizing said electroresponsive device it a second train enters said block from either end.

15. A continuous indication block signal system comprising a track divided into block sections, an electro-responsive device associated with each block section, train controlling circuits controlled by said electroresponsive' devices, means for energizing said electro-responsive device when a train enters the block pertaining thereto, and means for deenergizing said device When a second train enters said block before the latter has been cleared by the first train.

16. In a continuous indication train controlling system, a track divided into block sections, sources of current and track relays connected to said sections, a conductor parallel to the track divided into correspondin sections, means controlled by the track relays for supplying signaling energy to the conductor sections in accordance with traflic conditions, said means being rcsponsive to the entry of a second vehicle into an occupied block.

17. A continuous indication train controlling system comprising a track divided into block sections, sources of current and track relays connected to said sections, a conductor parallel to the track divided into corresponding sections, a vehicle having a contact engaging said conductor and having an electro-responsive device connected to said contact adapted to control suitable govern ing means, means controlled by said track relays for supplying signaling energy to said conductor sections when a vehicle is travelling under clear trat'fic conditions in the blocks pertaining thereto, said means being under the control of a second vehicle entering an occupied block.

18. A continuous indication train controlling system comprising a track divided into block sections, sources of current and track relays connected to said sections, a conductor parallel to the track divided into corresponding sections, a vehicle having a contact en gaging said conductor and an electro-responsivc device connected to said contact adapted to control suitable vehicle governing means, connections controlled by said track relays for supplying signaling energy to said conductor sections in accordance with trafiic conditions, and an electro-responsive device associated with each block section under the control of track relays and controlling said connections, said electro-responsive device being controlled by a second vehicle entering an occupied block to prevent said second vehicle from receiving a clear indication.

19. A continuous indication train controlling system comprising a track divided into block sections, sources of current and track relays connected to said sections, a conductor parallel to the track divided into sections, a vehicle having a contact engaging said conductor and an electro-responsive de vice connected to said contact adapted to control suitable indication means, means for supplying signaling energy to said conductor sections in accordance with traffic conditions, and means to atlect the supply of signaling energy When a second vehicle enters an occupied block.

20. A continuous indication train controlling system comprising a track divided into block sections, sources of current and track relays connected to said sections, a conductor parallel to the track, a vehicle having a contact engaging said conductor and an electro-responsive device connected to said contact adapted to control suitable indication means, means controlled by said track relays for supplying signaling energy to said conductor, said means being responsive to the entry of a second vehicle into an occupied block to prevent said second vehicle from receiving a clear indication.

21. In a continuous indication train con trolling system, a track divided into block sections, sources of current and track relays connected to said sections, a conductor parallel. to the track divided. into corresponding sections, means controlled by the track relays for supplying signaling energy to the conductor sections, and means to afiect the energy being supplied to a conductor section When the block pertaining thereto is occupied and a second vehicle enters said block.

22. In a continuous indication train controlling system, a track divided into block sections, sources of current and track relays connected to said sections, a conductor parallel to the track divided into corresponding sections, means controlled by the track relays for supplying signaling energy to the conductor sections, vehicles travelling on said track having contacts engaging said conductor and having electro-responsive devices connected to said contacts, said means being responsive toa following vehicle to control the signaling energy being supplied to the vehicle in advance thereof.

93. In a continuous indication train controlling system, a track divided into block sections, sources of current and track relays connected to said sections, a conductor parallel to the track, means controlled by the track relays for supplying signaling energy to said conductor, vehicles travelling on said track having contacts engaging said conductor and having electroresponsive devices connected to said contacts, said means being actuated when a following vehicle approaches within a predetermined zoneof the vehicle in advance to control the signaling energy being supplied to the vehicle in ad- Vance.

24:. In a continuous indication train controlling system, a track, sources of current and track relays connected to said track, a

conductor parallel to the track, means controlled by the track relays for supplying signaling energy to said conductor, vehicles travelling on said track having contacts engaging said conductor and having electroresponsive devices connected to said contacts, said means being responsive to a following vehicle and being actuated when said following vehicle approaches within a predetermined zone of the vehicle in advance to control the signaling energy being supplied to said vehicle in advance. I

25. In a continuous indication train con trolling system, a track, sources of current and relays connected to said track, a conductor parallel to the track, means controlled by the track relays for supplying signaling energy to said conductor, vehicles traveling on said track having electro-responsive devices adapted to be energized from said conductor, 'said means being responsive to a signature.

EDWARD C. SASNETT. 

